Securing BGP: A Case Study (8)

Throughout the last several months, I’ve been building a set of posts examining securing BGP as a sort of case study around protocol and/or system design. The point of this series of posts isn’t to find a way to secure BGP specifically, but rather to look at the kinds of problems we need to think…

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Rethinking BGP path validation (part 2)

This is the second post in the two part series on BGP path validation over on the LinkedIn Engineering blog. We left off last time after having described the eight operational requirements that must be met for any system that reduces our reliance on transitive trust in relation to the AS Path. As a reminder,…

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Reaction: BGP convergence, divergence & the ‘net

Let’s have a little talk about BGP convergence. We tend to make a number of assumptions about the Internet, and sometimes these assumptions don’t always stand up to critical analysis. . . . On the Internet anyone can communicate with anyone else – right? -via APNIC Geoff Huston’s recent article on the reality of Internet…

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Strong Reactions and Complexity

In the realm of network design—especially in the realm of security—we often react so strongly against a perceived threat, or so quickly to solve a perceived problem, that we fail to look for the tradeoffs. If you haven’t found the tradeoffs, you haven’t looked hard enough—or, as Dr. Little says, you have to ask what is gained and what is lost, rather than just what is gained. This failure to look at both sides often results in untold amounts of technical debt and complexity being dumped into network designs (and application implementations), causing outages and failures long after these decisions are made.

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The 4D Network

I think we can all agree networks have become too complex—and this complexity is a result of the network often becoming the “final dumping ground” of every problem that seems like it might impact more than one system, or everything no-one else can figure out how to solve. It’s rather humorous, in fact, to see a lot of server and application folks sitting around saying “this networking stuff is so complex—let’s design something better and simpler in our bespoke overlay…” and then falling into the same complexity traps as they start facing the real problems of policy and scale.

This complexity cannot be “automated away.” It can be smeared over with intent, but we’re going to find—soon enough—that smearing intent on top of complexity just makes for a dirty kitchen and a sub-standard meal.

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